Adjustable impact casing for a shaft furnace

ABSTRACT

An adjustable impact casing for use in a shaft furnace is formed of a plurality of upwardly extending segments. The segments are arranged into an inner circular row enclosed by an outer circular row. In each row, the segments are spaced angularly apart and are offset to the segments in the other row with their upwardly extending edges arranged in overlapping and substantially contacting relationship. The segments are pivotally supported about axes arranged transversely of the upright axis of the casing and the segments in the inner row are secured to one drive arrangement while the segments in the outer row are secured to another but similar drive arrangement. The two drive arrangements are controlled for moving the segments so that a time delay is provided between the movement of the segments in the inner row and the movement of the segments in the outer row.

United States Patent Schwerdtfeger et al.

ADJUSTABLE IMPACT CASING FOR A SHAFT FURNACE Primary Examiner-John J.Camby Attorney-Toren & McGeady [5 7] ABSTRACT An adjustable impactcasing for use in a shaft furnace is formed of a plurality of upwardlyextending segments. The segments are arranged into an inner circular rowenclosed by an outer circular row. in each row, the segments are spacedangularly apart and are offset to the segments in the other row withtheir upwardly extending edges arranged in overlapping and substantiallycontacting relationship. The segments are pivotally supported about axesarranged transversely of the upright axis of the casing and the segmentsin the inner row are secured to one drive arrangement while the segmentsin the outer row are secured to another but similar drive arrangement.The two drive arrangements are controlled for moving the segments sothat a time delay is provided between the movement of the segments inthe inner row and the movement of the segments in the outer row.

PATENTEDsEm I972 SHEET 1 BF 4 TORNEY SUMMARY OF THE INVENTION Thepresent invention is directed to an adjustable protection or impactcasing in a shaft furnace, particularly for use in blast furnaces, and,more especially, it concerns the arrangement of the casing made up oftwo circular rows of individual segments which are suspended for pivotalmovement into a desired position.

In known arrangements of the impact or protection casing within shaftfurnaces, the segments forming the casing are adjustable eitherindividually or jointly. In such casings the segments can be adjusted tovary the diameter of the casing and the angular disposition of itssurfaces so that the distribution of the furnace burden over the furnacecross section can be changed. The area that can be influenced, however,is small and involves essentially the annular area between the furnacewall and the outer edge of the furnace-top bell. In the circular areaunder the bell the distribution of the charge cannot be influenced. As aresult, this space is filled in accordance with the slope angle of thematerials charged into the furnace. As the size of furnace units becomelarger that portion of the area under the bell which cannot beinfluenced by the adjustable impact casing becomes increasingly largerrelative to the total charge cross section in the furnace.

To overcome this drawback in adjustable impact casings, it might besuggested that the adjustment angle of the casing be simply increased,especially for use in large furnaces. With such an arrangement, theburden materials could be deflected into annular areas the diameter ofwhich would be smaller than that of the furnace-top bell. However,difficulties are encountered with such wide angular adjustment ranges,since the segments of the casing are formed with a fixed radius. Inadjusting the pivotally suspended segments toward the center of thefurnace the radial clearance between the segments which overlap alongtheir lateral edges, is decreased. To afford an adjustment of thesegments over a wide range, in the position of the segments near thefurnace wall the radial clearance must be increased as the range ofadjustment is increased for the casing. In this regard the danger existsthat the burden material may become jammed between the individualsegments so that the adjustment of the casing is impeded. If the casingcannot be properly adjusted in position, then it will not be able toinfluence the charge in the furnace in the desired manner.

Therefore, it is the primary object of the present invention, to providean adjustable impact casing such that the disadvantages mentioned abovefor casing segments formed with a fixed radius are eliminated and arelatively wide range of adjustment is afforded.

In accordance with the present invention,the segments forming the casingare arranged in an inner circular row located adjacent an outer circularrow with the segments being controlled so that a time delay is providedbetween the segments in the inner row and in the outer row.

Based on this arrangement of the segments forming the casing, an inwardadjustment can be made, first, by moving the segments in the inner rowinto the desired position and then moving the segments in the outer row.When the segments are displaced outwardly the positioning procedure isreversed. In this impact casing arrangement, a predetermined radialclearance between the segments in the inner row and outer row can bedispensed with, since in each position within the range of adjustment ofthe segments they can be arranged so that they meet or contact alongtheir upright lateral edges. Accordingly, the difficulties experienced 0in the past in adjusting segments formed with a fixed radius areavoided, especially where a relatively wide range of adjustment isinvolved.

In this proposed arrangement, the segments within each of the rows canbe operated individually or jointly, and controls of hydraulic,pneumatic or electrical types can be connected in combination with atime delay for moving the segments in one row before the segments in theother row can be moved. It is advantageous to connect the positioningdrives for the segments of the inner row to one control unit and thepositioning drives of the segments of the outer row to another controlcircuit and to interconnect the control circuits via a time-delay relay.As an alternative arrangement for positioning the segments, theindividual positioning elements for each segment in one row can beconnected to a ring-shaped member and the controls for the individualrings interconnected through a time-delay so that first the segments inone of the rows are positioned followed by the positioning of thesegments in the other row.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this disclosure. For a better understanding of the invention,its operating advantages and specific objects attained by its use,reference should be had to the accompanying drawings and descriptivematter in which there are illustrated and described preferredembodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a partial vertical cross sectional view of the top of a blastfurnace incorporating the present invention;

FIG. 2 is a cross sectional view taken along the line II-II in FIG. 1;

FIG. 3 is a view similar to FIG. 1 but illustrating another embodimentof the invention; and

FIG. 4 is a schematic showing of the positioning arrangement inaccordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION In FIGS. 1 and 3, the upper partof a blast furnace is illustrated with an adjustable impact casing inaccordance with the present invention. The charge is directed into thefurnace through its throat I when the furnace-top bell 2 is lowered,note the closed position shown in full lines and the lowered or openedposition shown in dot-dash lines. Based on the diameter of the casingand the angular disposition of its surface, the charge directed into theblast furnace is given a certain profile as indicated in FIGS. 1 and 3.

The impact casing is formed of an inner row of impact-resistant segments3 having a fixed radius and an outer row of impact-resistant segments 30of a fixed radius with the lateral upright edges arranged in overlappingrelationship. As can be noted in FIG. 2, the

the inner row of segments. The fixed radius of the segments isdetermined based on the furnace radius for an .intermediate position inthe adjustment range of the segments.

Each of the segments 3, 3a is suspended within the shaft casing 4 of theblast furnace by means of rods 5 which are pivotally connected adjacenttheir upper ends of the inner surface of the shaft casing. On theoutwardly facing side of the segments a mounting member 6 is positionedand a push rod 7 is connected to each mounting 6 in a pivotal manner.Furnace wall 9 of the-shaft casing 4 disposed opposite the impact cas-"ing has'a plurality of funnel-shaped openings 8 through which the pushrod -7 extends outwardly. At its outer end, each push rod is secured,through a hinged joint,

to one arm 10 of an angle lever and the other arm 11 of the angle leveris connected to the lower end of a piston rod 12. The piston rod ismovably positionable within an hydraulic cylinder 13 supported on theexterior wall of the shaft casing. As indicated schematically in FIG. 4,the hydraulic cylinders 13 are operated by a control member 14. Thesegments 3 arranged in angularly spaced relationship within the innerrow of the casing are adjusted in position by means of the piston rod12, the arms 10, l l of the angle lever, and the push rod 7 so that theycan be pivotally displaced through the connection of the bar 5 to theinterior of the shaft casing 4 for varying the angle of inclination ofthe segment to the vertical axis of the casing and also for varying thedistance of the segment from the center of the shaft casing. Similarhydraulic cylinders l3aand controls 14a are provided for positioning thesegments 3a arranged in angularly spaced relationship within the outerrow of the casing.

In accordance with the present invention, the controls 14 for thehydraulic cylinders 13 of the segments 3 forming the inner row, areconnected to the controls 14a for the hydraulic cylinders 13a of thesegments 30 in the outer row so that a time differential is providedbetween the adjustment of the segments in one row as compared to thosein the other. In FIG. 4, a circuit for operating the controls of thehydraulic cylinders 13, 13a is illustrated. For sake of clarity onlythree of each type of cylinders is shown in FIG. 4. The hydrauliccylinders 13 are connected in parallel within a control circuit 15 whichconsists of a hydraulic system. The control 14 for operating thehydraulic cylinders 13 is positioned within the control circuit 15. Ifcontrol 14 receives a control pulse, the pressure medium is: fed to thehydraulic cylinders 13 via a pump 16 for selectively displacing thepiston rods 12 and adjusting the position of the segments 3 in the innerrow of the casing. The hydraulic cylinders 13a are arranged in a similarcontrol circuit 15a, as shown in FIG. 4. The controls 14, 14a areinterconnected by means of a time-delay relay 17. By means of this relay17, the hydraulic cylinders 13 can be actuated first for effecting theinward movements of the segments 3 in the inner row and, after they havebeen located in the desired position, the hydraulic cylinders 13a can beactuated so that the segments 3a in the outer row are moved intocontacting engagement with the segments in the inner row. Though notshown in FIG. 4, the control circuits 15, 15a would include safetyvalves of the type well known in the art.

As shown in FIG. 1, to move the segments 3 from the position shown insolid lines into the position pivotally displaced inwardly or to theright as shown in clot-dash lines, the hydraulic cylinders 13 areoperated by the controls 14 from a control console, not shown. As aresult, the segments 3 are displaced inwardly into the desired position.After the time-delay or difference provided by the relay 17, thesegments 3a are displaced inwardly until they contact the segments 3 inthe inner row and are positioned as close together as is possible. Inthis arrangement for moving the segments 3, 3a, the possibility of theimpact casing becoming jammed by burden materials is avoided. By meansof this adjustment procedure, the impact shell can be movably adjustedwithout difficulty over, a wide range, and the inclination of thesegments can be provided with an angle of 45 or more to the vertical.Depending on the length of the segments, for a blast furnace having ashaft casing diameter of 11 m it is possible to provide an adjustmentrange of 1,900 mm.

In FIG. 3, another embodiment of adjusting apparatus is illustratedcomprising a pair of ring-shaped members 19, 19a supported on brackets18 on the exterior surface of the blast furnace wall. The member 19 ispositioned above the push rod 7 while the member 19a is positioned belowthe push rods. Each of the rings 19, 19a can be rotated about the shaftcasing of the furnace by means of one or several hydraulic drives, 20,20a respectively, which are also mounted on the exterior of the shaftcasing in a manner not illustrated. All of the push rods 7 connected tothe segments in the inner row are connected to one of the rings 19, 19aand the push rods for the other row of segments are connected to theother one of the members 19, 19a. Linkage arrangements 21, 21a areprovided between the rings 19, 19a respectively, and their correspondingpush rods for transmitting the rotational movement of the rings to thepush rods and, in turn, to the segments in the inner and outer rows. Therings 19, 19a are controlled by an arrangement similar to that shown inFIG. 4, and when one ring is rotated or moved angularly about thefurnace, each of the segments connected to its through the push rods is,accordingly, selectively positioned. By means of the'time-delay device,as shown in FIG. 4, the

segments in one row can be positioned relative to those in the other rowwith a time differential.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the inventiveprinciples, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:

1. An adjustable impact casing for use in a shaft furnace, particularlyfor a blast furnace, said casing having an upright axis and comprising aplurality of angularly spaced apart first arcuate segments forming aninner row about the casing axis, a plurality of angularly spaced apartsecond segments forming an outer row about the casing axis and disposedcontiguous to said inner row, the axis of said first segments and secondsegments extending in the direction of the casing axis being offsetrelative to one another and with their lateral edges extending in thedirection of the casing axis being arranged in overlapping substantiallycontacting relationship so that said inner row and outer row of segmentsform a continuous casing surface, means for supporting said first andsecond segments, each of said first and second segments being pivotallymounted on said means adjacent the upper end of the segment, a pluralityof push rods extending transversely of the casing axis and each saidpush rod being secured to a different one of said first and secondsegments, means attached to each said push rod for displacing said pushrod transversely of the casing axis and for pivoting said segmentsattached thereto, a first control device secured to said means fordisplacing said push rods secured to said first segments, a secondcontrol device secured to said means for displacing said push rodssecured to said second segments, and means interconnecting said firstand second control devices for effecting the displacement of said firstand second segments with a time-delay between the movement of the innerrow of said first segments and the outer row of said second segments.

2. An adjustable impact casing, as set forth in claim 1, characterizedtherein that said push rods being secured to said first and secondsegments at positions spaced downwardly from the location of themounting of said segments.

3. An adjustable impact casing, as set forth in claim 1, characterizedin that said first control device comprises a first control circuitinterconnecting each of said means for displacing said push rods securedto said first segments, a first control located in said first controlcircuit, said second control device comprises a second control circuitinterconnecting each of said means for displacing said push rods securedto said second segments, a second control located within said secondcontrol circuit, and said means interconnected between said first andsecond control devices comprises a time-delay relay interconnecting saidfirst control and said second control.

4. An adjustable impact casing, as set forth in claim 1, characterizedin that said means for displacing said push rods transversely comprisinga first ring member located about and outwardly from said casing, afirst drive member secured to said first ring member for rotating itabout its central axis, first means connected to said first ring memberand to said push rods secured to said first segments for transmittingthe movement of said first ring member to said first segments forpivotally displacing said first segments, a second ring member locatedabout and outwardly from said casing, a second drive member secured tosaid first ring member for rotating it about its central axis, secondmeans connected to said second ring member and to said push rods securedto said second segments for transmitting the movement of said secondring member to said second segments for pivotally displacing said secondsegments.

5. An adjustable impact casing, as set forth in claim 1, characterizedin that said means for displacing said push rods transversely of theaxis of said casing comprising first hydraulic cylinders for said pushrods connected to said first segments, second hydraulic cylinders forsaid push rods connected to said second segments, linkages providedbetween said first and second hydraulic cylinders and said push rods fortransmitting the movement of said hydraulic cylinders to said push rodsand in turn for pivoting said first and second segn u u 6. An ad ustableImpact casing, as set forth In claim UNITED STATES PATENT (SFFICECERTIFICATE OF CORRECTIQN Patn O, 3, 93,952 7 Dated September 26 1972Invehtor(s) GUNTER SCHWERDTFEGER and BRUNO KAMMERLING It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

In the heading of the patent insert -[73] Assignee: GutehoffnungshuetteSterkrade A.G.

Ober'hausen-Sterkrade, Germany-- Signed and sealed this 1st day of May1973 (SEAL) Attest:

EDWARD M.FLETGHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents FORM PO-IOSO (10-69) vUS(IOMM-DC 60376-P69 v u.s GOVERNMENTPRINTING OFFICE: I969 O356-334,

1. An adjustable impact casing for use in a shaft furnace, particularlyfor a blast furnace, said casing having an upright axis and comprising aplurality of angularly spaced apart first arcuate segments forming aninner row about the casing axis, a plurality of angularly spaced apartsecond segments forming an outer row about the casing axis and disposedcontiguous to said inner row, the axis of said first segments and secondsegments extending in the direction of the casing axis being offsetrelative to one another and with their lateral edges extending in thedirection of the casing axis being arranged in overlapping substantiallycontacting relationship so that said inner row and outer row of segmentsform a continuous casing surface, means for supporting said first andsecond segments, each of said first and second segments being pivotallymounted on said means adjacent the upper end of the segment, a pluralityof push rods extending transversely of the casing axis and each saidpush rod being secured to a different one of said first and secondsegments, means attached to each said push rod for displacing said pushrod transversely of the casing axis and for pivoting said segmentsattached thereto, a first control device secured to said means fordisplacing said push rods secured to said first segments, a secondcontrol device secured to said means for displacing said push rodssecured to said second segments, and means interconnecting said firstand second control devices for effecting the displacement of said firstand second segments with a time-delay between the movement of the innerrow of said first segments and the outer row of said second segments. 2.An adjustable impact casing, as set forth in claim 1, chAracterizedtherein that said push rods being secured to said first and secondsegments at positions spaced downwardly from the location of themounting of said segments.
 3. An adjustable impact casing, as set forthin claim 1, characterized in that said first control device comprises afirst control circuit interconnecting each of said means for displacingsaid push rods secured to said first segments, a first control locatedin said first control circuit, said second control device comprises asecond control circuit interconnecting each of said means for displacingsaid push rods secured to said second segments, a second control locatedwithin said second control circuit, and said means interconnectedbetween said first and second control devices comprises a time-delayrelay interconnecting said first control and said second control.
 4. Anadjustable impact casing, as set forth in claim 1, characterized in thatsaid means for displacing said push rods transversely comprising a firstring member located about and outwardly from said casing, a first drivemember secured to said first ring member for rotating it about itscentral axis, first means connected to said first ring member and tosaid push rods secured to said first segments for transmitting themovement of said first ring member to said first segments for pivotallydisplacing said first segments, a second ring member located about andoutwardly from said casing, a second drive member secured to said firstring member for rotating it about its central axis, second meansconnected to said second ring member and to said push rods secured tosaid second segments for transmitting the movement of said second ringmember to said second segments for pivotally displacing said secondsegments.
 5. An adjustable impact casing, as set forth in claim 1,characterized in that said means for displacing said push rodstransversely of the axis of said casing comprising first hydrauliccylinders for said push rods connected to said first segments, secondhydraulic cylinders for said push rods connected to said secondsegments, linkages provided between said first and second hydrauliccylinders and said push rods for transmitting the movement of saidhydraulic cylinders to said push rods and in turn for pivoting saidfirst and second segments.
 6. An adjustable impact casing, as set forthin claim 1, characterized in that a furnace wall being laterallydisposed about and spaced outwardly from said casing, said furnace wallhaving a plurality of openings therein forming passages for said pushrods extending outwardly from said segments, said means for supportingsaid first and second segments being fixed to the interior of saidfurnace wall above the openings through said wall, and said meansopenings displacing said push rods tranversely of the casing axis beinglocated on the exterior surface of said furnace wall.